By Gabriel Partos
BBC South-east Europe analyst
It has been a busy weekend for Serbia's police.
Marko Milosevic is on the run, now his mother could join him
They have made a number of arrests, including that of a former deputy head of the secret police, Milorad Bracanovic, who was dismissed from his post in January.
According to the police, Mr Bracanovic is being investigated for alleged links to the so-called Zemun clan - one of Belgrade's two biggest mafia groups - which has been accused of having masterminded Mr Djindjic's murder.
Like several figures in the Zemun gang, Mr Bracanovic was formerly a senior officer in the now-disbanded Special Operations Unit (JSO) - a paramilitary police unit set up under Slobodan Milosevic to fight alongside Serb irregulars in Croatia, Bosnia and Kosovo.
Another of the Red Berets, Zvezdan Jovanovic - JSO deputy commander until his arrest last month - has now reportedly confessed to having pulled the trigger in Mr Djindjic's shooting.
This has now encouraged Interior Minister Dusan Mihajlovic to say that court proceedings leading to a trial can now get underway.
Meanwhile, police have also arrested three lawyers - including a former judge - on suspicion of using unlawful means to stop the prosecution or trials of leading members of the Zemun clan.
Their detention reinforces earlier claims that organised crime not only enjoyed the support of the Milosevic-era special police, such as the JSO, but also benefited from the services of members of the legal profession.
On Friday night, the Belgrade authorities announced that they had issued an arrest warrant for Mira Markovic, wife and chief adviser to Mr Milosevic over three decades.
The warrant for Ms Markovic follows the discovery of the remains of ex-President Ivan Stambolic who disappeared two-and-a-half years ago when Mr Milosevic was president.
The authorities reported 10 days ago that they had arrested four of Mr Stambolic's alleged abductors and killers - all of them ex-JSO - suggesting that the perpetrators had acted on the instructions of the former presidential couple.
Ms Markovic is currently in Moscow and the extradition process may take some time.
Besides, she could also go on the run - as her son, Marko Milosevic, has done for well over two years.
Two of those arrested, Jovica Stanisic (left) and Franko Simatovic, could be handed over to The Hague
He is believed to be in Russia, and an international arrest warrant has just been issued for him.
For Ms Markovic, though, there is a difficult dilemma - if she tries to avoid Serbian justice, she will not be able to pay her regular visits to her husband who is on trial for genocide and war crimes in The Hague.
As part of the crackdown on organised crime, the Serbian authorities have questioned over 7,000 people and some 2,000 are still in detention.
It is a huge operation which is supported by most Serbs.
But human rights organisations and some foreign governments are beginning to express concern about the state of emergency which has made the arrests possible.
Belgrade has said it will lift the state of emergency by the end of the month.